Is the height/plasma creatinine formula of Schwartz useful as a screening test in detecting Nigeria children with low GFR?

A group of 42 children with renal diseases seen at the University College Hospital Ibadan were studied in order to evaluate the usefulness of the height/plasma creatinine formula of Schwartz et al i.e. GFR ml/min/1.73 m2 = 0.55 x Height (cm)/Plasma creatinine (mg/dl) in identifying children with renal impairment. The children were divided into 2 groups of those with GFR as measured by endogenous creatinine clearance (Ccr) < 60 ml/min/1.73 cm2 and those with CCr > 60 ml/min/1.73 cm2. There were 21 children in each group. In detecting patients with Ccr less than 60 ml/min/1.73 m2, Schwartz formula had a sensitivity of 52%, a specificity of 100%, a positive predictive value of 100% and a negative predictive value of 68%. It is concluded that in detecting patients with impaired renal function who may need more accurate methods of estimating GFR, Schwartz formula has a low sensitivity and therefore may not be useful as a screening method.